var scrollMoveObj = null,
scrollPageY = 0,
scrollY = 0;
var scrollDivList = new Array();
    // obj需要添加滚动条的对象 w滚动条宽度 className滚动条样式名称
    // obj元素 必须指定高度，并设置overflow:hidden;
    // 如要兼容IE6 必须给obj元素 指定 overflow:hidden;
     var lpTab = document.getElementById("lp-map-tab");
    // var obj2 = $('.lpm-footer-4').get(0);
     jsScroll(lpTab, 5, 'divScrollBar');
    // jsScroll(obj2,5, 'divScrollBar');
        
     
    function jsScroll(obj, w, className) {
        if (typeof(obj) == 'string') {
            obj = document.getElementById(obj);
        }
        //当内容未超出现在高度时，不添加滚动条    
        if (!obj || obj.scrollHeight <= obj.clientHeight || obj.clientHeight == 0) {
            return;
        }  
        obj.scrollBarWidth = w || 6;
        obj.style.overflow = 'hidden';
        obj.scrollBar = document.createElement('div');
        document.body.appendChild(obj.scrollBar);
        obj.scrollBarIndex = document.createElement('div');
        obj.scrollBar.appendChild(obj.scrollBarIndex);
        obj.scrollBar.style.position = 'absolute';
        obj.scrollBarIndex.style.position = 'absolute';
        obj.scrollBar.className = className || '';
        if (!className) {
            obj.scrollBar.style.backgroundColor = '#ddd';
            obj.scrollBarIndex.style.backgroundColor = '#aaa';
        }

        scrollDivList.push(obj);
        scrollResetSize(obj);

        //使用鼠标滚轮滚动
        obj.scrollBar.scrollDiv = obj;
        obj.scrollBarIndex.scrollDiv = obj;
        obj.onmousewheel = scrollMove;
        obj.scrollBar.onmousewheel = scrollMove;
        obj.scrollBarIndex.onmousewheel = scrollMove;
        if (obj.addEventListener) {
            obj.addEventListener('DOMMouseScroll', scrollMove, false);
        }

        //拖动滚动条滚动
        obj.scrollBarIndex.onmousedown = function(evt) {
            evt = evt || event;
            scrollPageY = evt.clientY;
            scrollY = this.scrollDiv.scrollTop;
            isScrollMove = true;
            document.body.onselectstart = function() {
                return false
            };
            scrollMoveObj = this.scrollDiv;
            if (this.scrollDiv.scrollBar.className == '') {
                this.scrollDiv.scrollBarIndex.style.backgroundColor = '#888';
            }
            return false;
        }
    }

    //当页面大小发生变化时，重新计算滚动条位置
    window.onresize = function() {
        for (var i = 0; i < scrollDivList.length; i++) {
            scrollResetSize(scrollDivList[i]);
        }
    }

    //计算滚动条位置

    function scrollResetSize(o) {
        if (o.scrollHeight <= o.clientHeight) {
            o.scrollTop = 0;
            o.scrollBar.style.display = 'none';
        } else {
            o.scrollBar.style.display = 'block';
        }
        var x = 0,
            y = 0;
        var p = o;
        while (p) {
            x += p.offsetLeft;
            y += p.offsetTop;
            p = p.offsetParent;
        }
        var borderTop = parseInt(o.style.borderTopWidth || 0);
        var borderBottom = parseInt(o.style.borderBottomWidth || 0);
        o.scrollBar.style.width = o.scrollBarWidth + 'px';
        o.scrollBar.style.height = o.clientHeight + 'px';
        o.scrollBar.style.top = y + borderTop + 'px';
        o.scrollBar.style.left = x + o.offsetWidth - o.scrollBarWidth + 'px';
        o.scrollBarIndex.style.width = o.scrollBarWidth + 'px';
        var h = o.clientHeight - (o.scrollHeight - o.clientHeight);
        //当滚动条滑块最小20个像素
        if (h < 20) {
            h = 20;
        }
        o.scrollBarHeight = h;
        o.scrollBarIndex.style.height = h + 'px';
        o.scrollBarIndex.style.left = '0px';
        setScrollPosition(o);
    }

    function setScrollPosition(o) {
        o.scrollBarIndex.style.top = (o.clientHeight - o.scrollBarHeight) * o.scrollTop / (o.scrollHeight - o.clientHeight) + 'px';
    }

    document.documentElement.onmousemove = function(evt) {
        if (!scrollMoveObj) return;
        evt = evt || event;
        var per = (scrollMoveObj.scrollHeight - scrollMoveObj.clientHeight) / (scrollMoveObj.clientHeight - scrollMoveObj.scrollBarHeight)
        scrollMoveObj.scrollTop = scrollY - (scrollPageY - evt.clientY) * per;
        setScrollPosition(scrollMoveObj);
    }
    document.documentElement.onmouseup = function(evt) {
        if (!scrollMoveObj) return;
        if (scrollMoveObj.scrollBar.className == '') {
            scrollMoveObj.scrollBarIndex.style.backgroundColor = '#aaa';
        }
        scrollMoveObj = null;
        document.body.onselectstart = function() {
            return true
        };
    }

    // 鼠标滚轮滚动

    function scrollMove(evt) {
        var div = this.scrollDiv || this;
        if (div.scrollHeight <= div.clientHeight) return true;
        evt = evt || event;
        var b = true;
        if (evt.wheelDelta) {
            b = evt.wheelDelta > 0 ? false : true;
        } else {
            b = evt.detail < 0 ? false : true;
        }
        var step = 20;
        if (b) {
            if (div.scrollTop >= (div.scrollHeight - div.clientHeight)) return true;
            div.scrollTop += step;
        } else {
            if (div.scrollTop == 0) return true;
            div.scrollTop -= step;
        }
        setScrollPosition(div);

        if (evt.preventDefault) {
            evt.preventDefault();
        }
        return false;
    }